Cycle News is a weekly magazine that covers all aspects of motorcycling including Supercross, Motocross and MotoGP as well as new motorcycles
Issue link: https://magazine.cyclenews.com/i/1400350
FEATURE I PROTON KR3 P90 were not all his own making. Backing and the name Mode- nas came from a Malaysian scoot- er manufacturer, but the technol- ogy was British, and inspired by the light and agile three-cylinder Honda on which young Freddie Spencer narrowly beat Kenny's own more powerful V4 Yamaha in 1983. Kenny knew to his cost just how effective better braking and corner speed could be in a sustained season-long battle. The rules were helpful, with a minimum weight of 253 pounds for a triple compared with 286 pounds for a four-cylinder. Team Roberts engineers, led by the late Australian Warren Willing, developed and modern- ized the idea, but renowned race-car engineer Tom Walkin- shaw, his TWR firm prominent in the English "Formula One Belt" surrounding Team Roberts's Banbury base, was responsible for final design and manufacture of the V3 engine. Work started during 1996, and when the bike took to the tracks in 1997, it was condemned to go through early development very much in public. This proved rather embarrassing, for there were many teething troubles and breakdowns for the riders, French ex-off-road superstar Jean-Michel Bayle and Kenny's eldest son Kenny Junior. Results up against the estab- lished and experienced Honda, Yamaha and Suzuki were now and then respectable: Bayle qualified on the front row at Brno W hat was life like in the sometimes 24-hour Ban- bury sweat-shop where Kenny Roberts built his grand prix bikes? For O'Kane, "they were the best years of my career." At Kenny's insistence, everything was custom made. "For example, choosing a power-valve motor. You could go to your local Yamaha racing spares shop and buy the ones for the YZR 250. Trouble is they would look identical to the Yamaha's, and it would look–at the very least–like we'd copied them. So, I ended up designing them from scratch. We had a carbon housing, some Swiss DC motors, and every- thing was custom made. "The electrical generators, most of the parts for them came from a company in England making disc brakes for mountain bikes. I went to them because none of the engi- neering companies in the Midlands had time for small, fiddly items. They were all too busy doing F1 stuff or bigger projects. So our gen- erator rotor was put together using bicycle crank tools, funnily enough, the spanners for bicycles. "That was one of my jobs for the two-stroke period. "At that time, we were having debates on which way to spin the crankshaft, so we had primary chains and sprockets made [in addi- tion to the established gear primary drive]. In one practice session, with Mike Hale riding, we did one run with sprockets, then clutch off, cover off, sprockets off and primary gears on, and on the other side the trigger wheel for the ignition. Then the bike went out with the crank running in the opposite direction. We did that in one practice session. Really good information… same bike, same rider, same tires, same session. The other factories were also experimenting like that, but I doubt very much ever on the same bike in the same session." Roberts ran his team light and lean. He also ran them very, very hard during the initial stages of the KR3 build. THE BANBURY SWEAT-SHOP